Knee control for sewing machines



Dec. 28, 1937. N. T. sAwDEY ET AL KNEE CONTROL FOR SEWING MACHINES Filed July 25, 1935 iwi m w m mym m mum wmm 56 A 5 LI. Hm NM m N@ Y B Patented Dec. 28, 1937 UNITED STATES PATENT OFFICE Neil T. Sawdey, Shaker Heights, and Nathaniel Colegrove, Lakewood, Ohio, assignors to White Sewing Machine Corporation, Cleveland,

Ohio, a corporation of Delaware Application July 25, 1935, Serial No. 33,106

11 Claims.

This invention relates to a sewing machine and particularly to a knee-actuated device for operatlng or regulating the control mechanism of an electrically powered sewing machine.

Electrically powered sewing machines are controlled in their speeds of operation and in their starting and stopping by suitable control mechanisms arranged in the electric circuits for the motors and usually consisting of suitable rheostats, switches, or the like.

It is desirable that the control mechanisms be operated or regulated by means which can be actuated by the knee of the operator, wherefore his hands are free to perform a variety of other functions incident to the operation of the sewing machines.

An object of the invention is to provide a kneeactuated device for operating or regulating the electrical control mechanism of an electrically powered sewing machine, which device is efficient and simple in operation, and is composed .of relatively few parts.

Another object is to provide a knee-actuated device of the character specified wherein the element which is contacted by the knee of the operator can be adjusted to positions most convenient for the operator.

A further object of the invention is to provide a knee-actuated device of the character specified which operates freely with a minimum of friction and without likelihood of the moving parts of the device binding or sticking in guideways or similar members since the device eliminates sliding parts.

Another object is to provide a device of the character specified which is relatively small in size and is so shaped that it can be associated with a sewing machine cabinet, particularly a cabinet of the drop leaf or drop head type, in a location such that it does not interfere with any of the other parts of the sewing machine or with the raising and lowering of the machine head and does not detract from the appearance of the cabinet.

Further and additional objects and advantages inherent in the invention and not specifically referred to above will either be pointed out or become apparent during the following detailed description of an embodiment of the invention which is illustrated in the accompanying drawing, wherein Fig. 1 is a perspective View of a sewing machine of the drop leaf or drop head cabinet type;

Fig. 2 is a detached top plan view of a device embodying the invention, the movable parts of the device being shown in the positions they occupy when the machine is idle;

Fig. 3 is a view similar to Fig. 2, except that certain portions of the device are broken away and shown in section, while the movable parts of the device are shown in the positions they occupy when the machine is operating at its top speed;

Fig. 4 is a sectional view taken substantially on line 4-4 01' Fig, 2, looking in the direction of the arrows;

Fig. 5 is a fragmentary elevational view taken in the direction of the arrows from line 5-5 of Fig. 4;

Fig. 6 is a sectional view taken substantially on line 6-6 of Fig. 3, looking in the direction of the arrows; and

Fig. '7 is a detached detail perspective view of one of the elements of the device.

The knee-actuated device embodying the present invention is shown by way of illustration as mounted upon a sewing machine cabinet of the drop leaf or drop head type, but it will be understood that the device is applicable to other types of sewing machines and cabinets.

The cabinet shown in Fig. 1 is indicated generally by the numeral l0 and, as is well understood in the art, the sewing machine head H is mounted on a swinging platform l2 which is pivoted along one of its edges to swing upwardly or downwardly into the cabinet so that the sewing machine head H can be raised above the level of the table in operating position or lowered into the space defined by the side and back walls and top of the table of the cabinet for the inoperative and idle position.

As previously stated, the sewing machine is electrically powered and is driven by means of a suitable electric motor located in the head I I or in any other suitable place. In electrically operated sewing machines, it is customary to employ suitable rheostats, switches, or the like for controlling the starting and stopping and the speeds of operation of the driving motor for the machine.

Simply by way of illustration the machine shown in Fig. 1 has a rheostat l3 and a control switch I4 therefor located within the cabinet and forming the control mechanism for the driving motor, the switch l4 being arranged at the front of the cabinet.

The locations of the rheostat and the switch and the construction thereof do not per se form any part of the present invention, and such location and construction of the rheostat and the switch, in fact, form the subject matter of a separate application for Letters Patent.

As will be later pointed out, the knee-actuated device embodying the present invention is shown operatively associated with the switch I4, but it should be understood, however, that in some instances the switch might be eliminated and the device be operatively associated with the rheostat. In any event, the control mechanism with which the device is associated should be preferably of the type having an oscillatable or rockable gontrol or actuating shaft.

The knee-actuated device embodying thepresent invention is secured within the cabinet at the front side thereof, and, as shown in Fig. 1, the device is substantially completely concealed, the element which is contacted by the operators knee being substantially the only portion of the device which is exposed to view even when the doors at the front of the cabinet are opened.

The device comprises an elongated channelshaped supporting member I5 which is fixedly secured by its base to the cabinet adjacent the front thereof so as to face inwardly of the recess therein. The supporting member I5, when secured in position, is concealed and, if necessary, the portion of the cabinet to which it is secured may be recessed or cut away to partially receive the supporting member.

The lower horizontal arm of the supporting member adjacent one end thereof has the horizontal arm of an angle bracket I6 secured to its under side (see Fig. 6) while the switch I4 is secured to the inner side of the vertical arm of the bracket I6.

The arms of the supporting member I5 have fixed therein a vertically extending pivot pin I! which is in vertical alignment with'the oscillatable shaft I8 of the switch I4. A similar pivot pin I9 is fixed in the arms of the member I5 a suitable distance from the pin I1 and adjacent the opposite end of the member I5.

A pair of channel-shaped hinge brackets 20 having at their opposite ends extended side wall portions 2| are arranged with the portions 2| at one end of the brackets lying between the arms of the supporting member I5 and pivotally supported upon the pivot pins I1 and I9, which extend through aligned openings in the portions 2 I.

The portions 2I at the opposite ends of the hinge brackets 20 are located between the arms of an outwardly facing channel member 22 preferably of shorter length than the supporting member I5 and are pivotally supported upon pivot pins 23 and 24 carried by the arms of the member 22 adjacent the ends thereof and passing through the aligned openings in the portions 2|. 1

It will be seen from the description thus far set forth that the member 22 is hingedly connected to the supporting member l5 through the hinge brackets 20 and said member 22 and the hinge bracketscan move relative to the member I5 with what might be termed a parallelogram movement.

The pivot pin 24 is located at the end of the member 22 which is adjacent the switch I4 and is free to rotate in the arms of the member 22 and is provided at its lower end below the lower arm of the member 22 with an enlarged portion 25 (see Fig. 6). The portion 25 of the pin 24 extends through a longitudinally extending slot located adjacent the outer end and at the longitudinal center line of a lever arm 26 which has its opposite end fixed to the upper end of the oscillatable shaft I8 of the switch I4.

It will be apparent that when the member 22 is moved the lever arm 26 will move therewith to rock the shaft I8 of the switch, it being remembered that the axis of the shaft l8 which forms the pivotal axis of the arm 26 is coincident with the pin I! about which pivots the hinge bracket 20 at the right-hand end of the device as viewed in the drawing.

In order to provide suitable means for limiting the movement of the member 22 in opposite directions at points which are correlated to the extreme limits of movement of the operative parts of the switch I4, the. following construction is employed. A stop bracket 21 of suitable length, and in the form of an angle, has its horizontal arm extending beneath and secured to the under side of the upper horizontal arm of the supporting member I5 intermediate the ends of said member while the vertical arm of the stop bracket 21 extends upwardly above the member I5 at the inner side thereof (see Fig. 4). A stop bracket 28, shorter in length than the bracket 21 but also in the form of an angle, has its horizontal arm secured to the upper side of the upper arm of the member 22 intermediate the ends of said member, while its vertical arm extends upwardly above the member in a plane parallel to the plane of the vertically extending arm of the bracket 21. The vertical arm of the stop bracket 28 has secured thereto a pad 29 of suitable soft or shock absorbing material adapted to contact the vertical arm of the stop bracket 21 when the member 22 is at the limits of its movement in opposite directions, it being remembered that said limits of movement of the member are reached simultaneously as the lever arm 26 reaches the limits of its movement in operating the switch I4.

A coil spring 30 surrounds the pin I9 and has one of its ends bearing against the base of the supporting member I5 and its opposite end bearing against the base of the hinge bracket 20. A second coil spring 3| surrounds the pin 24 and has one of its ends bearing against the base of the member 22 and its opposite end bearing against the base of the adjacent hinge bracket 20. The purpose of the springs 30 and 3| is to normally urge the member 22 to its most lefthand position, as viewed in the drawing, wherein the switch I4 is in the "off position and the driving motor for the sewing machine is idle.

The member 22 is actuated in opposite directions to operate the control switch I4 by means of an element 32 which is contacted by the knee of the operator and extends downwardly from the member 22.

The element 32 preferably is substantially flat but has rounded or beveled edges and ends so as to present no obstructions which might result in tearing the clothes or stockings of the operator of the machine. The upper end of the element 32 is pivotally connected by means of a pivot screw 33 to a horizontally extending portion 34 of a clamping bracket, which comprises, in addition to the portion 34, a part 35 extending at right angles from said portion and having its upper end channel-shaped and interfitting the channel .of the member 22. The portion 34 extends transversely of the members I5 and 22, while the part 35 lies parallel to said members.

A substantially z shaped bracket 36 has two of its arms embracing'the outside of the member 22 while its third arm bears against and is secured to the part 35 of the clamping bracket by means of a bolt 31 and nut 38.

It willbe understood that the clamping bracket and the Z-shaped bracket 36 can be clamped by means of the bolt 31 and nut 38 to the member 22 .in any desired position of adjustment along the length of the member, and since the element 32 is connected to the clamping bracket, said element may, in turn, be adjusted to a position to suit the convenience of the operator.

It will be noted that the element 32 is pivoted on an axis parallel with the members I! and 22, wherefore said element can swing from the vertical position into the recess in the cabinet. This arrangement possesses the advantage that, should the door of the cabinet be swung shut when the element 32 is in a position to be engaged by the door, said element would simply swing into the recess in the cabinet and would not mar or damage the door.

As previously stated, the operator can adjust the clamping bracket and the bracket 36 along the member 22 to a position such that the element 32 is located for the most convenient operation. When the operator of the sewing machine wishes to start the operation of the machine, it is merely necessary for him to press his knee against the element 32 to cause a movement of the member 22 from the position shown in Fig. 12 toward the position shown in Fig. 3. The movement of the member 22 acts through the switch II to start the operation of the motor, and it will be understood that continued movement of the member 22 will act through the switch to increase the operating speed of the motor until its maximum speed has been attained, at which time the stop bracket 28 engages the stop bracket 21 as shown in Fig. 3. The operator may readily start and stop the motor and increase or diminish the speed thereof by pressing the knee against the element 32 to move it and the member 22 in one direction or by removing the knee pressure from the element to allow the springs 30 and 3| to function to move the member 22 and the element 32 in the opposite direction.

Inasmuch as the pin l1 and the shaft I8 preferably but not necessarily are in axial alignment, the pin 24 and the end of the lever arm 26 swing in concentric and similar arcs and hence there is no necessity in the device embodying the invention to translate the movement of the member 22 and element 32 into a different form of movement to accomplish the actuation of the switch M.

The device embodying the invention has extreme ease of operation since there are no sliding parts to stick in guideways and the like. Also the device is simple as no translation of movement from one form to another is required.

Although a preferred embodiment of the invention has been illustrated and described herein, it should be understood that the invention is susceptible of various modifications and adaptations within the scope of the appended claims.

Having thus described our invention, we claim:

1. A device for operating the control mechanism of an electrically powered sewing machine comprising a fixed member, a pair of hinge brackets pivotally mounted on said member and spaced longitudinally thereof, a movable member hingedly connected to said brackets and adapted to have an operative connection to said control mechanism, and a depending knee actuated element operatively connected with said movable member.

2. A device for operating the control mechanism of an electrically powered sewing machine comprising a fixed member, a pair of hinge brackets pivotally carried by said fixed member and spaced longitudinally thereof, a movable member pivotally carried by the outer ends of said hinge brackets, means for limiting the movement of said movable member in opposite directions, and a depending knee actuated element operatively connected with said movable member.

3. A device for operating the control mechanism of an electrically powered sewing machine comprising a fixed member, a pair of hinge brackets pivotally carried by said fixed member and spaced longitudinally thereof, a movable member pivotally mounted on the outer ends of said hinge brackets, and a depending knee actuated ele ment operatively and adjustably connected with said movable member.

4. A device for operating the control mechanism of an electrically powered sewing machine and of the type having an oscillatable control shaft comprising a fixed member, a pair of hinge brackets pivotally secured to said member and spaced longitudinally thereof, the pivotal axis of one of said brackets lying in axial alignment with said control shaft, a movable member pivotally carried by the outer ends of said hinge brackets and adapted to have an operative connection with said control shaft, and a depending knee actuated element operatively connected with said movable member.

5. A device for operating the control mechanism of an electrically powered sewing machine comprising a fixed member, a pair of hinge brackets pivotally secured to said member and spaced longitudinally thereof, a movable member pivotally mounted on the outer ends of said hinge brackets and adapted to have an operative connection with said control mechanism, spring means for normally urging said hinge brackets and said movable member in one direction, and a depending knee actuated element operatively connected with said movable member.

6. A device for operating the control mechanism of an electrically powered sewing machine comprising a fixed member, a pair of hinge brackets pivotally mounted on said member and spaced longitudinally thereof, a movable member hingedly mounted on the outer ends of said hinge brackets and adapted to be operatively connected to said control mechanism, stop means for limiting the movement of said hinge brackets and said movable member in opposite directions, spring means acting to normally move said brackets and said movable member to their limit of moveent in one direction, and a depending knee actuated element operatively connected to said movable member.

'7. A device for operating the control mechanism of an electrically powered sewing machine and of the type having an oscillatable control shaft comprising a fixed member, a pair of hinge brackets pivotally mounted on said member, the pivotal axis of one of said hinge brackets being arranged in axial alignment with said control shaft, a movable member pivotally mounted on the outer ends of said hinge brackets, a lever arm secured to said control shaft and adapted to have an operative connection with said movable member such that said connection during movement of said member moves in an arc concentric with said control shaft, and a depending knee actuated element operatively connected with said movable member.

8. A device for operating the control mechanism of an electrically powered sewing machine comprising a channel-shaped member adapted to be fixedly connected to the machine, a pair of hinge brackets pivotaliy mounted within the channel of said member, an oppositely facing channel-shaped and movable member pivotally.

mounted on the outer ends of said hinge brackets and adapted to have an operative connection with said control mechanism, and a depending knee actuated element operatively connected with said movable member.

9. A device for operating the control mechanism 'of an electrically powered sewing machine comprising a channel-shaped member adapted to be fixedly secured to the machine, a pair of hinge brackets pivotally mounted within the channel of said member, an oppositely facing channelshaped member pivotally mounted on the outer ends of said hinge brackets and adapted to have an operative connection with said control mechanism, means for limiting movement of said last named member and said hinge brackets in opposite directions, and a depending knee actuated element operatively connected with said last named member.

10. A device for operating the control mechanism of an electrically powered sewing machine comprising a channel-shaped member adapted to be fixedly secured to the-machine, a pair of hinge amass? brackets pivotally mounted within the channel of said member and spaced longitudinally thereof,

an oppositely facing channel-shaped member pivotally mounted on the outer ends of said hinge v brackets, stop means for limiting movement of said last named member and said hinge brackets in opposite directions, spring means acting to normally hold said last named member and said brackets at the limit of their movement in one direction, and a' depending knee actuated element operatively connected with said member.

11. A device for operating the control mechanism of an electrically powered sewing machine comprising a channel-shaped member adapted to be fixedly secured to the machine, a pair of hinge brackets pivotally mounted within the channel of said member and spaced longitudinally thereof, an oppositely facing channel-shaped member pivotaliy mounted on the outer ends of said hinge brackets and adapted to have an operative connection with said control mechanism, and a de- 

